The Spain international has scored four goals in his first three Premier League games, helping the west London side take maximum points to go top of the table.
Things are going very well for me at Chelsea and that encourages me to keep improving
Costa, who moved to Chelsea from Atletico Madrid in a £32m deal in July, endured a tough summer after the 25-year-old failed to score in the World Cup as the holders crashed out at the group stage.
And the Brazilian-born forward admits he need to replicate his Chelsea form at international level after Spain suffered a 1-0 defeat by France on Thursday night.
“I really want to score with Spain,” Costa told Marca.
“Our game is to have the ball a lot, have a lot of possession. I am aware that I have to adapt to them.
“Things are going very well for me at Chelsea and that encourages me to keep improving.”
Costa scored 27 goals in 35 La Liga appearances to help Atletico win the title last season.
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